280 Responses to “Bu Hafta”

sometimes I feel as if we need a Madame Defarge with her knitting needles recording the names of the deniers in a scarf … but I was reading Northrop Frye today and came upon this:

“In interviews i am almost invariably asked at some point whether I feel optimistic or pessimistic about some contemporary situation. The answer is that these imbecile words are euphemisms for manic-depressive highs and lows, and that anyone who struggles for sanity avoids both.”

it seems to me that many people are going through the pop-psych grief cycle: denial, anger, bargaining, depression, acceptance; and we don’t all go through it at the same rate, enough to sift the news as you are doing

and as acceptance comes then is time to face the music and get on with building ‘wedgies’ or Stabilization Wedges if you like :-)

be well, I am sure glad that you are doing the work that you are doing.

One of the problems with new blogs hoping to raise awareness about global warming, is that the delusionists come out of the woodwork and try to turn it into a debate over the truth or falsehood of anthropogenic climate change.

In fact, they still show up regularly here! But they don’t come here that often, or stay very long, because the readers here are quite knowledgeable, and usually deliver a speedy and effective “smackdown.” So, their efforts to cloud the issue on RC generally make them look like idiots — which, I suppose, they are.

Whether or not the Nature blog will descend into pointless argument depends greatly on how the moderators handle delusionists, and how knowledgeable the regular readers are. Until they can develop a well-informed core readership (like RC has), it’s up to the mods to deliver the smackdown when idiotic comments come in.

â�¢ Science appeared to have trumped politics, delegates said
â�¢ Environmental groups hail report as a “roadmap” and that it is time to act
â�¢ China had pushed for lowest targets, delayed action
â�¢ Much of debate centered around costs of adopting greener policies

As the problems get more extreme, and our knowledge of them get more precise, and the projections into the future get more accurate, the science deniers will get more desperate. We’re starting to see that now. It will only get worse. This is a ‘War on Science’, just one of many concurrent wars. It’s going to get nasty.

Either you are willing to fight, or you aren’t. I see a lot of highly educated and knowledgeable people who are simply not willing to fight for fear of losing their jobs. Once they come to the harsh realization that if things continue the way they are going, they won’t have any jobs, then they seem willing to fight. It takes an extraordinary amount of intelligence to see that big picture, a level that most ordinary scientists simply don’t have, immersed in their specialties and lives as they are.

In a press release, the US Public Interest Research Group (US PIRG) says this about the latest IPCC report:

To prevent dangerous global warming (as documented in the second volume of the IPCCâ��s report), global emissions would need to peak no later than 2015 and then decline by as much as 50 percent by 2050, thereby limiting the global average temperature increase to about 2 degrees Centigrade over pre-industrial levels … While not specified in today’s release, the U.S. must reduce its emissions by at least 80 percent by 2050 to meet the global target of about 50 percent reductions, given our greater contribution to the problem.

Would anyone care to place bets as to what year global emissions will peak and then begin to decline?

“No later than 2015” means we have no more than eight years in which to slow, stop and then reverse the present accelerating growth in emissions. Is that likely?

Where does he claim we don’t know what humans have contributed to atmospheric c02?
“in this graph it starts in 1928, at 1.1 gigatons (i.e. 1.1 billion metric tons). It peaks in 1929 at 1.17 gigatons. The world, led by its mightiest power, the USA, plummets into the Great Depression, and by 1932 human CO2 production has fallen to 0.88 gigatons a year, a 30 per cent drop. Hard times drove a tougher bargain than all the counsels of Al Gore or the jeremiads of the IPCC (Inter-Governmental Panel on Climate Change). Then, in 1933 it began to climb slowly again, up to 0.9 gigatons.”

And the other line, the one ascending so evenly? That’s the concentration of CO2 in the atmosphere, parts per million (ppm) by volume, moving in 1928 from just under 306, hitting 306 in 1929, to 307 in 1932 and on up. Boom and bust, the line heads up steadily. These days it’s at 380.There are, to be sure, seasonal variations in CO2, as measured since 1958 by the instruments on Mauna Loa, Hawai’i. (Pre-1958 measurements are of air bubbles trapped in glacial ice.) Summer and winter vary steadily by about 5 ppm, reflecting photosynthesis cycles. The two lines on that graph proclaim that a whopping 30 per cent cut in man-made CO2 emissions didn’t even cause a 1 ppm drop in the atmosphere’s CO2. Thus it is impossible to assert that the increase in atmospheric CO2 stems from human burning of fossil fuels.

Reason through graceful explanations always trumps name calling and idiotic statements. I watched G. Beck’s show “climate of fear”, who claims he wants a debate on AGW theory, its nice that he wants one since there was none on his program. There were a few jabs against common sense as usual, like Christies
Kilimanjaro was melting during Hemingway’s days, Wikipedia explains:

” the mountain for the past 11,700 years are rapidly disappearing. Over the past century, the ice cap volume has dropped by more than 80%
a study led by Ohio State University ice core paleoclimatologist Lonnie Thompson [2] predicted that ice on top of Africa’s tallest peak would be gone between 2015 and 2020 [3] [4]. In 2007 a team of Austrian scientists from University of Innsbruck predicted that the plateau ice cap will be gone by 2040, but some ice on the slope will remain longer due to local weather conditions ”

Over the same past Century humans have been dumping CO2 in the atmosphere. Many other glaciers to date from all over the world are loosing their ice as well. A debate would be nice Mr Beck!

With respect to the Nature blog, I’m not sure I agree with Lambert so much. First, just because the IPCC says that most of the warming in the last 30 years is anthropogenic doesn’t mean that trends in only the last 30 years are relevant. Does it? I mean, that is starting from a depressed baseline (due to anthropogenic cooling). Second, I personally (although I have no expertise in the matter) agree with Von Storch and Zorita’s view that greater interest in the (higher) variance in the handle portion of the hockeystick is a good thing. I hope a lot of new, widely dispersed, and representative proxies are developed for analysis.

[Response: That’s motherhood and apple pie. We are all of course interested in that (see e.g. this piece by the PAGES/CLIVAR intersection working group, Mann, M.E., Briffa, K.R., Jones, P.D., Kiefer, T., Kull, C., Wanner, H., Past Millennia Climate Variability, Eos, 87, 526-527, 2006). Problem is that Von Storch and Zorita are a red herring (and a highly problematic one at that–see e.g. the previous discussions of the problems in their analyses on site here and here. – mike]

Unfortunately I was trapped in a doctor’s waiting room the other day and subjected to many repetitions of the commercial for Glenn Beck’s “Climate of Fear” episode. Of course I then had to watch some of it. At the very beginning of the episode, he stated that this was not going to be a balanced view. Sure enough, the show was neither balanced nor truthful. I think it’s rather sad that CNN would allow such misinformation under the guise of opinion on their news show. In my view, it significantly diminishes their whole organization’s credibility. This was one step below FOX presenting the lunar landing as a hoax. Somewhat ironically, after I watched a few minutes of the Glenn’s misguided and misleading episode, I became extremely nauseous, cancelled my plans to drive to dinner, turned off the TV, turned out the lights, and went to bed.

The two lines on that graph proclaim that a whopping 30 per cent cut in man-made CO2 emissions didn’t even cause a 1 ppm drop in the atmosphere’s CO2.
Dana:

Why should a cut in CO2 emissions necessarily cause the atmospheric CO2 level to drop? Does your bathtub suddenly become empty when you turn down the water? To achieve negative growth in CO2 in the atmosphere, emissions would have to be cut to less than the amount being absorbed by the oceans and other sinks. I don’t believe oceans were absorbing 70% of fossil fuel emissions in the 1930s, nor at any time since.

I haven’t yet seen an explicit refutation of Cockburn’s argument about the Great Depression of the thirties.

First of all, is what he says accurate? How closely can we estimate Carbon Dioxide production during those years? How accurate are the readings from ice cores for such a short period of time? I still haven’t found a reference discussing the details.

But let’s suppose he is describing the graphs approximately correctly. My explanation would go something like the following. Cokcburn imagines that scientists are treating the atmosphere as a fixed reservoir to which CO_2 is added by human activity. He then claims it can’t be building up from such activity because it didn’t drop when the activity dropped for a few years. Presumably he doesn’t worry about where the extra CO_2 went during this time. (Gremlins anyone?) But, the concentration of CO_2 in the atmosphere is dependent on how the Carbon cycle operates. The contributions by human activities such as burning fossil fuels, clearing land, and cement production are a relatively small part of the mix. So it is not a simply a matter of adding CO_2 to a reservoir which would otherwise be fixed. Human contributions are a perturbation to a complex dynamic system. To determine the repsonse, you need a model, and construction of such models is what Carbon cycle specialists do. From the little I’ve read on the subject, they have a pretty good understanding of how the system functions, and have concluded the effect of the perturbation is pretty much what has been observed.

In other words, his argument would be like arguing that the accepted theory of the tides is wrong because tides don’t follow the moon exactly.

Read this letter — written years ago—- from Donella Meadows to John Sununu, if you want to learn more:

“A Letter to a Very Smart Man

“Dear John Sununu,

“I know how smart you are. I know about your engineering degree, and I watched you perform as my governor all those years before you went to the White House. I’ve seen your mind snap up information, quick as a trap. Therefore I was surprised the other day when you made a statement unworthy of your mental abilities….

” … Picture a huge bathtub half full of water. Now imagine 110 gallons of water a minute pouring in through the faucet and 110 gallons a minute pouring out through the drain. Water flows through the tub like crazy, but the level stays constant. Now turn the input flow up by five gallons a minute. What happens? The water in the tub starts to rise. It will keep going up, as long as that extra five gallons is flowing in — until it spills over and makes a big mess.

“That’s what’s happening to the CO2 in the atmosphere. It has risen from 270 to 350 parts per million, and it’s still rising. And we’re not leaving the faucet alone; we’re turning it on ever faster….”

#10. Strawman. Miss Dana wrote “Thus it is impossible to assert that the increase in atmospheric CO2 stems from human burning of fossil fuels.”

Wow… I, personally, could not understand what you were saying. Your post is all over the place, bases its evidence on undesignated “charts”, strange people called “he” and the use of extremist words like “jeremiads.”

Anyway, Miss Dana, could you please say who “he” is and what “chart” “he” is refering to so we can at least have a basis for discussion?

For the sixth time or seventh time, people on this website have asked you to please read this site’s material before acting like you or (Beck, is is it?) know more than all the peer-review publishing scientists from the world’s 89 at least countries who can prove in peer-review what they are talking about as part of a body of evidence started in 1842 (Fourier)?

To refresh your memory please read either the 2007 IPCC documents (not the charts which some non-publishing, non-scientist says is the truth), and the following links:

Finally … Alexander Cockburn has shown that obdurate scientific illiteracy is not a trait reserved to those on the starboard side of the political spectrum.

It’s been awfully uncomfortable of late having to listen to fellow Republicans indulge in a kind of political correctness that somehow compels them to deny the validity of evidence for the human role in climate change. In so doing, they have forsaken true conservatism, which is all about restraining physical appetites, taking responsibility for one’s actions, avoiding unnecessary risks, practicing frugality, and being good stewards.

Please do not assume that the politicians and poseurs who cling to absurd arguments in denying a human role in climate change are “conservatives.” They may think they are; they most certainly are not.

Thanks for the interesting post – RealClimate continues to be an excellent source for solid climate change information. I recently saw Christopher Horner on Glenn Beck’s show saying that we haven’t experienced any warming since 1998! Of course, he failed to discuss the contribution of ENSO. In fact, he was wrong anyway since according to NASA, 2005 was the warmest year in more than a century (see http://www.nasa.gov/vision/earth/environment/2005_warmest.html)
It is refreshing to see Real Climate confronting disinformation in the media.

Dana, the guy you’re quoting is wrong. And you didn’t even read what he wrote.

You said you couldn’t find the graph. Here’s what the article says:

“Now imagine two lines on a piece of graph paper. ”

Okay? Can you understand where the graph is? He’s asking you to imagine it.

Then he tells you something about that picture. What he tells you is simply wrong.

It takes upwards of a century for CO2 to go away (and it’s not simple). Two things remove CO2 — photosynthesis, and weathering of rock. Before people started adding fossil fuel CO2, the level in the atmosphere was steady for some thousands of years (since the last ice age ended, roughly).

We reduce the extra CO2 people are adding, what happens? It accumulates slightly less rapidly.
After a century or two, you’ll see a difference worth talking about in the atmosphere.

Many people don’t understand this. There’s no shame in not understanding it. The shame is on the people who aren’t giving you accurate information or pointers to how to learn for yourself.

Try the links given you in the earlier post. Read some of the science. This isn’t simple, but it’s understandable.

Don’t be fooled by people who won’t give you sources where you can read for yourself what’s known and published in the science journals. Look for footnotes. Read some. See if they’re right.

Keep posting, people. Those who knew there was human induced climate change long ago but no one really listened so they got a menial job and let the Phd’s do the talking can feel a little vindicated while we all perish together. The only meaningful thing the climate change is going to do for people is expedite nuclear war so that the suffering people are experiencing in places like Iraq and Sudan can be global, and the human condition when there is no food or water can really come out and show us who and what humans really are. The changing climate will make people kill other people, plain and simple. Look at the history books. Human induced climate change and global industrialization equals kaboom! Now, excuse me, I need to fry some doughnuts before my boss comes over and screams. While you go to your talks or whatever it is you do, and discuss this over coffee and scones, remember, the next generation will be suffering.

RE:#17 Back then I worked for John Sununu for his NH Fish & Game Department. It was pure turmoil, politically. He was for the power company and against our wildlife concerns. Sound familiar? It’s the same song from all of these folks so-inclined.

If you haven’t picked up a copy of the May 2007 Vanity Fair, do so. You’ll be surprised that their 2nd annual “Green Issue” is so thoroughly researched, in depth, and skewers the denialist machine better than I’ve ever seen done. There’s not much about the science, but if you want the real story about the politics and propaganda, this will knock your socks off.

Thanks Hank, you are right i ran off to find a graph that doesn’t exist in response to #18’s request for the graph! Sorry, i’m new to this being a musician i usually only have to keep track of where one is in the harmony and rhythm.
My interest has been picued by the media bliz
Do we have or is it possible to measure the actual heat generated by co2? Is there something like a thermometer for co2 heat?
I will use that bathtub analogy!
Thankyou for your well considered replies, Dana

I was interested to see what Nature had to say about your site but if you follow the RC links, the link to the the original “welcome” from Nature is broken. Just a minor point, but it’s the kind of thing your ditractors will jump on.

[Response: Thanks for the heads up. Fixed now. – mike]

I have been interested in this issue since the 80’s and I’m a long time fan of your site and the “republic of science” philosophy it embodies. The link would come in handy elswhere as refutation to those who often claim RC is some sort of political front intent on ripping off taxpayers.

Is this true?
” as the earth warms, carbon sinks will become carbon emitters. In other words, while nature is expected to decrease absorbing mankind’s CO2 emissions 30% by 2030, carbon now fixed in the ground is expected to reemit into the air.

Specifically, methane hydrate has TWICE the carbon of all other fossil fuel combined, and it is ice, so only needs to melt to emit (whereas other fossil fuel needs to be burned to emit).”

This was a comment posted at another link from one of the blog postings.

Libertarians like a Cartesian plane for determining political positions, but Cockburn, LaRouche and a few others are what Robert Anton Wilson called political non-Euclidians – maybe another axis would help though – Cockburn wouldn’t like it, but I’d put him and other denialists with most of the 9/11 conspiracy theorists and a few others at one end, and people who insist on the primacy of facts and reason at the other. Maybe we could call the Cockburn end “Trutharians” and us “Factarians.” We’re the superficially boring end.

If Peak Oil theory is to be believed, it would appear that the IPCC emission scenarios are much higher than can be expected. Or put another way, increasing energy prices caused by depleting fossil fuel reserves could create a de facto surcharge on carbon emissions.

[Response:There’s still plenty of coal, even if oil becomes scarce. David]

Re 26 Dana. Not quite what you were asking, but near … In our modelling we use temperature scales to define the temperatures of business, industry and economies, which is related to CO2 emission pathways. For example, one can look at the carbon downsizing curves and identify various phases that require execution. The initial phase is a turning phase, then a primary synchronisation phase, followed by several other phases as economies proceed to initial lock-down (ie severe emissions control). If an economy is targetting at a 2 degree Celcius rise then the carbon emissions will need to peak between 2010-2013 as the turning phase is executed. (There are a lot of complexities in this, relating to synergetic processes, resonances, scaling phenomena, etc, and those are modelled). Roughly, the temperature scales we use are 0-1000 days for 1 deg C, 1000-2000 days for 2 deg C, etc, for delivery of emissions peak. From this, one can scale through businesses and industries within an economy and identify equivalent temperatures which relate to their carbon downsizing activities. The temperature dependence can subsequently be related to Climate Change Richter Scales for global infrastructure, and from these business and industrial risk can be identified.

The opportunity over the next 1000 days is for hot corporations to realise they are overheating, and put in place and commence execution of a 1 degree C business plan. Considering that a typical corporation may have 200,000 upwards businesses in its global supplies networks, each 1 deg C corporation has the potential to bring about significant positive change worldwide.

A question that people may ask of the board members of a corporation is “what is the target temperature of the corporation, and please explain why the board has chosen a target temperature which is higher than 1 degree Celcius?”

A second question that people may ask of the board members is “what is the material business risk that the board has identified for different target temperatures and how and why have higher-than-1 degree Celcius business risks been discounted?”. These are the sort of questions (perhaps phrased somewhat differently) that insurers and reinsurers are asking, for example.

They are the sort of questions that stakeholders should be asking companies. As far as climate change is concerned, we are all stakeholders.

Re #9 , I keep on coming back to this very subject myself in many posts here at real climate. The USA needs to reduce greenhouse gas emissions by 80% by 2050, a seemingly insurmountable task I would suggest not least due to emerging economic growth and their available coal reserves. Carbon sequestration technology is slated to come online (just one plant mind) by 2012 on an industrial scale and its rollout will take x years and will need to become cheaper to in order for the market place to adopt it. Then their is americas vehicle fleet which takes around 10 to 15 years to replace. Cellular ethenol has yet to be really cracked and hence it cannot scale to more than a few percentage points of use over petrol, so we are talking 20 years before that technology is replace by even a small percentage. The list goes on and on.

Although yesterdays UN climate change conference does paint a apocolypse postponed picture of climate change due to the reports upbeat reporting by the UK media in general I for one am skeptical of its overall merits although I do concur that humanity might at last begine to start to get to grips with the emissions issues but it just might be too little to late. After all to date May 2007 very little has been done although the IPCC and other official bodies have been droning on about it for years. The present US administration needs to be gone before anything happens anyway and that is another 2 years away.

Thanks David Wilson [#1] for saying: “pop-psych grief cycle: denial, anger, bargaining, depression, acceptance”. Knowing the cause, or at least a first hypothesis about the cause, is a step in solving the problem. Another puzzle is: WHY do some people think that their own/human extinction is OK if “god” does it? Why do they think the extinction of Homo Sapiens is OK if “natural causes” are the cause of global warming? Could we get some psychologists to study this?

[[The two lines on that graph proclaim that a whopping 30 per cent cut in man-made CO2 emissions didn’t even cause a 1 ppm drop in the atmosphere’s CO2. Thus it is impossible to assert that the increase in atmospheric CO2 stems from human burning of fossil fuels. ]]

Not true. You are assuming ambient CO2 concentration is directly proportional to CO2 output. It isn’t. The fraction emitted every year is just a tiny proportion of the amount already out there. Ambient CO2 is 40% higher than when the industrial revolution started because the industrial revolution has had 250 years to work.

While the bathtub analogy provides some insight, it is in fact hopeless to try to understand what is happening to the Carbon Cycle as a result of human activities by a simple model. Try studying the discussion of Carbon Cycle dynamics in ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Ch07.pdf
to see how complicated it actually is. There are large fluxes in both directions between the atmosphere and the biosphere and between the atmosphere and the surface ocean. In each case, the fluxes back and forth are roughly in balance. Human activities contribute a steadily growing much smaller flux adding Carbon to the atmosphere which results in changes in the above mentioned fluxes, but not in any simple to explain way.

Also, instead of imagining graphs, as Cockburn suggests, it is helpful to look at actual graphs. The above report doesn’t discuss what happened in the thirties, but graphs of yearly increases in CO_2 concentration, as measured at Mauna Loa and in Antartica, show considerable variation from year to year. There is clearly no simple relation between the size of the increase in any given year and the amount of CO_2 emitted by burning fossil fuels.

The same article contains FAQ 7.1 which lays out the reasons why we know the observed increase in CO_2 arises primarily from human activity.

Oddly, when one clicks the “Google that” link from the post [http://www.google.com/search?q=CO2+lags+Temperature+ice+core&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a], the second choice, is the RealClimate post entitled “The lag between temperature and CO2. (Goreâ��s got it right.)” The address associated with this on the google listing, however is “www.realclimate.org/index.php/ archives/2007/04/barton-gets-it-wrong/” which is a nixie.

[Response: Thanks. It should be ok now (fixed using a redirect). This happens when the permalink didn’t get updated from the original draft and then propagates into the ether. -gavin]

Dana, here’s a brief excerpt from the Sterman&Sweeney paper, right on point.
This is what Wossname, Cockburn, is blithering ignorantly about. Whoever checks facts for his publication really blew it completely, utter nitwittery under his name.

“We found a widespread misunderstanding of climate change dynamics. Two-thirds of the subjects believed global temperature responds immediately to slight or dramatic changes in CO2 emissions. Still more believed that reducing emissions near current rates would stabilise the climate, when in fact emissions would continue to exceed removal, increasing greenhouse gas concentrations and radiative forcing.

“Low public support for policies to reduce emissions may be based more on misconceptions of climate dynamics than high discount rates (that is, putting a low value on the future) or uncertainty about the risks of harmful climate change.

“If greater resources were devoted to developing public understanding of the dynamics of climate change, citizens and policymakers would have a more reliable basis for assessing current and future climate policy proposals. ”
——– end quote ———

Re #31 (Bob Cousins): I don’t think you are reading the abstract of Kharecha and Hansen very accurately. They may be saying that what you say is true of oil alone but not of coal and “unconventional fossil fuels” (like oil from tar sands, I guess?). Hence their statement, “We suggest that, if estimates of oil and gas reserves by the Energy Information Administration are realistic, it is feasible to keep atmospheric CO2 from exceeding approximately 450 ppm, provided that future exploitation of the huge reservoirs of coal and unconventional fossil fuels incorporates carbon capture and sequestration. Existing coal-fired power plants, without sequestration, must be phased out before mid-century to achieve this limit on atmospheric CO2.”

So, they are arguing that reaching the peak in oil production may help…but it ain’t going to solve the problem all by itself. We still have to take action to avoid releasing the CO2 from coal and unconventional reserves into the atmosphere.

Leonard, to teach, start where people are, not where you wish they were. People show what they don’t understand; Dana gets it immediately when shown; Cockburn never got it at all, and writes nitwittery.

Where most people (including most graduate students) start from:

—- failing to understand even the bathtub analogy —

but it is understandable.

Once conservation of matter is understood in this context, progress can be made looking at the IPCC.
Not before. SSRN makes this available from four university sites and includes a link to email either the abstract or the full text to anyone you think could learn from it — an admirable presentation:

“… We presented highly educated graduate students with descriptions of greenhouse warming drawn from the IPCC’s nontechnical reports. Subjects were then asked to identify the likely response to various scenarios for CO 2 emissions or concentrations. The tasks require no mathematics, only an understanding of stocks and flows and basic facts about climate change. Overall performance was poor. Subjects often select trajectories that violate conservation of matter. Many believe temperature responds immediately to changes in CO 2 emissions or concentrations….”

Only 240 people have downloaded that paper, in all the years since it went online. That’s really sad.

just to keep the perspective straight, pete (33), the W. Bush administration has spent more on assessing and responding to (potential) global warming than all previous administrations put together. Also recall it was under Clinton/Gore that the Senate voted unanimously to can the Kyoto treaty.

“Thus, it is evident that most IPCC scenarios
implicitly assume that a large amount of unconventional or undiscovered resources will become a
viable substitute for dwindling conventional reserves.”

is what interests me. The maximum emissions modelled by Kharecha & Hansen are about half of the maximum emissions projected by the IPCC.

The Peak Oil adherents hold that these unconventional resources will be expensive to produce, and the undiscovered resources will be insignificant. The Peak Oil people think that the EIA estimates of energy resources are overly optimistic. A reduction in oil (and gas) production would cause all energy sources to become more expensive, suppressing demand. A regime of dwindling, expensive fossil fuel energy is quite different to the unlimited supplies envisaged by the IPCC.

The question I was wondering is does it matter that the IPCC are working with unrealistic emission scenarios.

There is another aspect of bathtub physics that is easily overlooked but may have some relevance for understanding changes in atmospheric CO2 concentrations:

As the water level in the tub rises, the rate of outflow through the drain also rises due to increased hydrostatic pressure (height of the water column). Likewise, if the inflow rate from the faucet is reduced to less than the outflow rate through the drain, the water level will start falling but outflow rate will decrease because the hydrostatic pressure is reduced.
This analogy applies to the rate of CO2 diffusion from the atmosphere into the ocean which is directly proportional to the partial pressure gradient (air –> ocean, assuming the ocean is a CO2 sink) in accordance with the Fick diffusion equation (http://en.wikipedia.org/wiki/Fick's_law_of_diffusion). As CO2 partial pressure in the atmosphere falls, the rate of CO2 diffusion into the oceans will also decrease. Many other factors influence CO2 uptake by the oceans, of course, but the physics of diffusion is fundamental to this process.

RE: Comment 5 “Has anyone seen the May 2007 article by Jack Barrett and David Bellamy? It’s in the Proceedings of the Institution of Civil Engineers and argues (like Monckton) that climate sensitivity is around 1C.”

Barrett and others have argued that there is a net negative feedback, not a net positive feedback to an increase in forcing, GHG or other.

The hypothesized negative feedback mechanism is an increase in low level clouds, due to higher evaporation. The higher evaporation is hypothesized to be a response to a warmer planet. (70% of the planet is covered with water.) Clouds reflect both short and long wave radiation. The reflected short wave radiation is not affected by GHG and hence passes back out to outer space.

The effect of a net negative feedback to an increase in forcing as opposed to a net positive feedback is to reduce rather than to amplify the forcing.

My understanding is the standard GCMs use a response to forcing of 0.75 +/- 0.25 C/W/m2 which would require that there would be a positive feedback response to an increase in forcing.

Others have argued that the planet’s response to forcing should be 0.2 C/W/m2 with a variance of about +/- 0.2C/W/m2. The lower response to an increasing in forcing would require negative as opposed to positive feedback.

The Sterman, John and Booth Sweeney, Linda, study suggests that decision makers will not take action on global warming until well after tipping points have been passed.

In fact, decision makers and leaders that really understood stocks and flows might have already worked out aggressive greenhouse gas control plans, because tipping points may already have passed unnoticed by the climate models.